Sadly there appears to be a decline in the numbers of hedgehogs generally throughout the British Isles for various reasons – increased chemical use possibly affecting food sources or directly poisoning the hedgehogs, road kills, and known predators such as badgers, foxes or domestic dogs. The good news is that you can increase your chances of attracting them to your garden by adopting some of the following practices:

Hazards

The first and most important step to take is to ensure that you eradicate potential hazards, so an organic approach is essential. Even the use of slug pellets can be highly toxic to wildlife and therefore, you have to decide which is the more important - wildlife or preservation of cultivated plants at all costs.

In addition wire netting, uncovered drains or grids into which a hedgehog might fall should be eliminated, as should any other trapping hazard - even a discarded can or yoghurt container can prove fatal to a hedgehog if it's head becomes trapped.

As with all animals a source of water is essential, but hedgehogs are not aquatic and therefore need to be able to escape if they access a pond.

If you intend to light bonfires, or perhaps clear an area of the garden with a mechanical cutter, do search for possible hedgehog inhabitants beforehand and remove to a place of safety.

Food

Insects are a main source of food for hedgehogs, and in the main insects do little harm in the garden in the long term. You can even encourage caterpillars, by planting the odd cabbage and then allowing nature to take it's course, rather than expecting perfect specimens for human food consumption. Worms thrive in compost heaps, so if possible allow access both into and out of your heap for the hedgehog to feed. If slugs and snails are a problem in your garden, encouraging a hedgehog to take up residence should pay dividends with natural predation. Some folk will provide a little dog or cat food as a supplement to the hedgehog's diet, but it is important to ensure that the animal does not completely rely on this source, and remember that such food might also attract other, less welcome visitors!

A small secure container at ground level, frequently topped up with water, should suffice as a source of liquid.

Habitat

An undisturbed habitat is essential, so try to set aside an area of your garden which is sheltered, and provides plenty of cover e.g. compost heap, shrub cuttings or a wood or leaf pile. This will give the hedgehog a natural home to retreat to. Even a garden shed with access beneath may become the cosy, dry and safe home of a hedgehog.

.... and finally

Remember that hedgehogs are generally nocturnal creatures and the only evidence you may have of their residence is their droppings. They hibernate between October and April and can be quite noisy if you happen to disturb their sleep!